Unable to connect to Hbase using Java API

I am using HDP 2.5 Single Node. And I am using OSX. The following is my java code in local. I am running it from eclipse. I create a table called as demo using the shell.

package hbase;

import java.io.IOException;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.ConnectionFactory;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.ResultScanner;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.client.Table;

public class Sample {

public static void main(String[] args) throws IOException{
	// Instantiating Configuration class
       System.out.println("Trying to connect...");

       Configuration conf = HBaseConfiguration.create();
       conf.set("hbase.zookeeper.quorum", "sandbox.hortonworks.com");
       conf.set("hbase.zookeeper.property.clientPort", "2181");
       System.out.println("HBase is running!");
	   
       Connection conn = ConnectionFactory.createConnection(conf);
       Table  table = conn.getTable(TableName.valueOf("demo"));
       Scan scan1 = new Scan();
       
       ResultScanner scanner1 = table.getScanner(scan1);
      
       for(Result res: scanner1){
    	   System.out.print(res);
       }
       
       System.out.println("Table created Successfully...");

}

}

And I get the following output
Trying to connect…
HBase is running!
log4j:WARN No appenders could be found for logger (org.apache.hadoop.metrics2.lib.MutableMetricsFactory).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
2017-03-22 22:52:33.427 java[31764:3853860] Unable to load realm mapping info from SCDynamicStore
Exception in thread “main” java.lang.RuntimeException: java.lang.RuntimeException: java.lang.NullPointerException
at org.apache.hadoop.hbase.client.RpcRetryingCaller.callWithoutRetries(RpcRetryingCaller.java:208)
at org.apache.hadoop.hbase.client.ClientScanner.call(ClientScanner.java:320)
at org.apache.hadoop.hbase.client.ClientScanner.nextScanner(ClientScanner.java:295)
at org.apache.hadoop.hbase.client.ClientScanner.initializeScannerInConstruction(ClientScanner.java:160)
at org.apache.hadoop.hbase.client.ClientScanner.(ClientScanner.java:155)
at org.apache.hadoop.hbase.client.HTable.getScanner(HTable.java:821)
at hbase.Sample.main(Sample.java:31)
Caused by: java.lang.RuntimeException: java.lang.NullPointerException
at org.apache.hadoop.hbase.client.RpcRetryingCaller.callWithoutRetries(RpcRetryingCaller.java:208)
at org.apache.hadoop.hbase.client.ClientSmallReversedScanner.loadCache(ClientSmallReversedScanner.java:211)
at org.apache.hadoop.hbase.client.ClientSmallReversedScanner.next(ClientSmallReversedScanner.java:185)
at org.apache.hadoop.hbase.client.ConnectionManager$HConnectionImplementation.locateRegionInMeta(ConnectionManager.java:1249)
at org.apache.hadoop.hbase.client.ConnectionManager$HConnectionImplementation.locateRegion(ConnectionManager.java:1155)
at org.apache.hadoop.hbase.client.RpcRetryingCallerWithReadReplicas.getRegionLocations(RpcRetryingCallerWithReadReplicas.java:300)
at org.apache.hadoop.hbase.client.ScannerCallableWithReplicas.call(ScannerCallableWithReplicas.java:151)
at org.apache.hadoop.hbase.client.ScannerCallableWithReplicas.call(ScannerCallableWithReplicas.java:59)
at org.apache.hadoop.hbase.client.RpcRetryingCaller.callWithoutRetries(RpcRetryingCaller.java:200)
… 6 more
Caused by: java.lang.NullPointerException
at org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher.getMetaReplicaNodes(ZooKeeperWatcher.java:395)
at org.apache.hadoop.hbase.zookeeper.MetaTableLocator.blockUntilAvailable(MetaTableLocator.java:553)
at org.apache.hadoop.hbase.client.ZooKeeperRegistry.getMetaRegionLocation(ZooKeeperRegistry.java:61)
at org.apache.hadoop.hbase.client.ConnectionManager$HConnectionImplementation.locateMeta(ConnectionManager.java:1185)
at org.apache.hadoop.hbase.client.ConnectionManager$HConnectionImplementation.locateRegion(ConnectionManager.java:1152)
at org.apache.hadoop.hbase.client.RpcRetryingCallerWithReadReplicas.getRegionLocations(RpcRetryingCallerWithReadReplicas.java:300)
at org.apache.hadoop.hbase.client.ScannerCallableWithReplicas.call(ScannerCallableWithReplicas.java:151)
at org.apache.hadoop.hbase.client.ScannerCallableWithReplicas.call(ScannerCallableWithReplicas.java:59)
at org.apache.hadoop.hbase.client.RpcRetryingCaller.callWithoutRetries(RpcRetryingCaller.java:200)
… 14 more

Please help